CN104518721A - Compressor control system of variable-frequency air conditioner and noise suppressing method of variable-frequency air conditioner compressor - Google Patents

Abstract

The invention discloses a compressor control system of a variable-frequency air conditioner. The compressor control system comprises a current sampling module, a position estimator, a speed correction module, a first coordinate conversion module, a first double-T network wave trap, a second double-T network wave trap, a current correcting module and a second coordinate conversion module, wherein the current sampling module samples three-phase current of a compressor, the position estimator acquires estimated angle and speed of a rotor, the speed correcting module corrects the estimated speed of the rotor to acquire q-axis target current, the first coordinate conversion module subjects the three-phase current to coordinate conversion to obtain direct-axis current and cross-axis current, the first double-T network wave trap and the second double-T network wave trap filter harmonic waves in the direct-axis current and the cross-axis current respectively, the current correcting module corrects the direct-axis current and the cross-axis current after filtering of the harmonic waves so as to obtain direct-axis voltage and cross-axis voltage, the second coordinate conversion module converts coordinates of the direct-axis voltage and the cross-axis voltage so as to obtain three-phase voltage. The compressor control system can effectively filter the harmonic waves of the current and suppresses noise of the compressor of the variable-frequency air conditioner. The invention further discloses a noise suppressing method of the variable-frequency air conditioner compressor.

Description

The compressor control system of convertible frequency air-conditioner and noise suppressing method thereof

Technical field

The present invention relates to household electrical appliance technical field, particularly a kind of compressor control system of convertible frequency air-conditioner and a kind of noise suppressing method of frequency converting air-conditioner compressor.

Background technology

Along with the raising of people's living standard, increasing family come into by convertible frequency air-conditioner.The comfortableness of air-conditioning and energy-saving effect are the important indicators of an evaluation heat pump performance, and noise level is then evaluate that of air conditioning comfortableness is important to be measured.The noise of compressor of air conditioner is one of main source of air conditioner noises, and it can be divided into mechanicalness noise, electromagnetic noise and gas dynamic property noise.

Wherein, current harmonics is the main contributor producing compressor of air conditioner electromagnetic noise, and reducing current harmonics is the effective ways suppressing compressor of air conditioner electromagnetic noise.But, in prior art, generally adopt low pass filter during filtering current harmonics, and the feature of low pass filter is, to the noise higher than cut-off frequency, along with the increase attenuation multiple of frequency increases gradually, and delayed phase also increases thereupon, therefore, can not filtering 3 times, 6 primary current harmonic waves effectively, thus effectively can not reduce the electromagnetic noise of compressor, reduce the comfortableness of air-conditioning.

Summary of the invention

Object of the present invention is intended to solve above-mentioned technological deficiency at least to a certain extent.

For this reason, one object of the present invention is the compressor control system proposing a kind of convertible frequency air-conditioner, and the compressor control system of this convertible frequency air-conditioner can effective filtering current harmonics, thus suppresses the noise of the compressor of convertible frequency air-conditioner, improves the comfort level of air-conditioning.

Another object of the present invention is the noise suppressing method proposing a kind of frequency converting air-conditioner compressor.

For achieving the above object, the compressor control system of a kind of convertible frequency air-conditioner that one aspect of the present invention embodiment proposes, comprising: current sample module, for three-phase current Ia, Ib, Ic of Sampling Compression machine; Position estimator, for estimating that the position of the rotor of described compressor and speed are with the estimating speed of the estimation angle and rotor that obtain rotor; Velocity correction module, for carrying out velocity correction to obtain quadrature axis target current Iqref according to described target velocity to the estimating speed of described rotor; First coordinate transferring, for carrying out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq to described three-phase current Ia, Ib, Ic; First twin-T network trapper and the second twin-T network trapper, described first twin-T network trapper is used for the harmonic wave in direct-axis current Id described in filtering, and described second twin-T network trapper is used for the harmonic wave in quadrature axis current Iq described in filtering; Current correction module, for carrying out current correction to obtain direct-axis voltage Vd and quadrature-axis voltage Vq to the direct-axis current Id after filtering harmonic wave and quadrature axis current Iq respectively according to d-axis target current Idref and described quadrature axis target current Iqref; Second coordinate transferring, for carrying out Coordinate Conversion to obtain three-phase voltage Va, Vb, Vc of controlling described compressor to described direct-axis voltage Vd and quadrature-axis voltage Vq.

According to the compressor control system of the convertible frequency air-conditioner that the embodiment of the present invention proposes, by three-phase current Ia, Ib, Ic of current sample module samples compressor, and utilize the position of the rotor of position estimator estimating compressor and speed with the estimating speed of the estimation angle and rotor that obtain rotor, thus velocity correction module carries out velocity correction to obtain quadrature axis target current Iqref according to target velocity to the estimating speed of rotor, also pass through the first coordinate transferring to three-phase current Ia simultaneously, Ib, Ic carries out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq, and by the harmonic wave in the first twin-T network trapper and the second twin-T network trapper difference filtering direct-axis current Id and the current harmonics in quadrature axis current Iq, thus current correction module carries out current correction to obtain direct-axis voltage Vd and quadrature-axis voltage Vq to the direct-axis current Id after filtering harmonic wave and quadrature axis current Iq respectively according to d-axis target current Idref and quadrature axis target current Iqref, and then, second coordinate transferring carries out Coordinate Conversion to obtain the three-phase voltage Va controlling compressor to direct-axis voltage Vd and quadrature-axis voltage Vq, Vb, Vc.Therefore, the compressor control system of convertible frequency air-conditioner of the present invention can current harmonics in filtering direct-axis current Id and quadrature axis current Iq, effectively suppress the noise of the compressor of convertible frequency air-conditioner, improve the comfort level of air-conditioning, and do not need to increase hardware cost, realize simple, resources of chip occupancy is low.

In one particular embodiment of the present invention, transfer function when described first twin-T network trapper and the second twin-T network trapper carry out filtering to the triple-frequency harmonics in described direct-axis current Id and quadrature axis current Iq respectively obtains according to following formula:

$D_3\left(S\right)=\frac{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+K\frac{5S}{\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

Further, transfer function when described first twin-T network trapper and the second twin-T network trapper carry out filtering to the fifth overtone in described direct-axis current Id and quadrature axis current Iq respectively obtains according to following formula:

$D_6\left(S\right)=\frac{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+K\frac{5S}{2\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

Particularly, the width of the filtering well head of described first twin-T network trapper and the second twin-T network trapper can be determined according to K.

In one embodiment of the invention, described second coordinate transferring comprises: inverse park coordinate transformation unit, carries out inverse park Coordinate Conversion to obtain two phase voltage Valpha, Vbeta for the estimation angle according to described rotor to described direct-axis voltage Vd and quadrature-axis voltage Vq; Inverse clarke coordinate transformation unit, for carrying out inverse clarke Coordinate Conversion to obtain described three-phase voltage Va, Vb, Vc to described two phase voltage Valpha, Vbeta.

Further, described first coordinate transferring comprises: clarke coordinate transformation unit, for carrying out clarke Coordinate Conversion to obtain biphase current Ialpha, Ibeta to described three-phase current Ia, Ib, Ic; Park coordinate transformation unit, carries out park Coordinate Conversion to obtain described direct-axis current Id and quadrature axis current Iq for the estimation angle according to described rotor to described biphase current Ialpha, Ibeta.

In an embodiment of the present invention, described position estimator is used for estimating that the position of the rotor of described compressor and speed are with the estimating speed of the estimation angle and described rotor that obtain described rotor according to described two phase voltage Valpha, Vbeta and described biphase current Ialpha, Ibeta.

For achieving the above object, the present invention on the other hand embodiment proposes a kind of noise suppressing method of frequency converting air-conditioner compressor, comprises the following steps: S1, samples to three-phase current Ia, Ib, Ic of compressor; S2, carries out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq to described three-phase current Ia, Ib, Ic; S3, carries out filtering to suppress noise during described compressor operating to the harmonic wave in described direct-axis current Id and quadrature axis current Iq respectively based on the first twin-T network trapper and the second twin-T network trapper.

According to the noise suppressing method of the frequency converting air-conditioner compressor that the embodiment of the present invention proposes, by sampling to three-phase current Ia, Ib, Ic of compressor, and Coordinate Conversion is carried out to obtain direct-axis current Id and quadrature axis current Iq to three-phase current Ia, Ib, Ic, thus respectively filtering is carried out to suppress electromagnetic noise during compressor operating to the current harmonics in direct-axis current Id and quadrature axis current Iq based on the first twin-T network trapper and the second twin-T network trapper.Therefore, the current harmonics during noise suppressing method of frequency converting air-conditioner compressor of the present invention effective filtering compressor operating in direct-axis current Id and quadrature axis current Iq, thus suppress the noise of the compressor of convertible frequency air-conditioner, improve the comfort level of air-conditioning.Further, the method is simple and reliable.

In one particular embodiment of the present invention, in step s3, when carrying out filtering to the triple-frequency harmonics in described direct-axis current Id and quadrature axis current Iq, the transfer function of described first twin-T network trapper and the second twin-T network trapper obtains according to following formula:

$D_3\left(S\right)=\frac{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+K\frac{5S}{\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

Further, in step s3, when carrying out filtering to the fifth overtone in described direct-axis current Id and quadrature axis current Iq, the transfer function of described first twin-T network trapper and the second twin-T network trapper obtains according to following formula:

$D_6\left(S\right)=\frac{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+K\frac{5S}{2\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

The aspect that the present invention adds and advantage will part provide in the following description, and part will become obvious from the following description, or be recognized by practice of the present invention.

Accompanying drawing explanation

The present invention above-mentioned and/or additional aspect and advantage will become obvious and easy understand from the following description of the accompanying drawings of embodiments, wherein:

Fig. 1 is the control principle schematic diagram of the compressor control system of convertible frequency air-conditioner according to the embodiment of the present invention;

Fig. 2 is the control principle schematic diagram of the compressor control system of convertible frequency air-conditioner according to the present invention's specific embodiment;

Fig. 3 is the flow chart of the noise suppressing method of frequency converting air-conditioner compressor according to the embodiment of the present invention;

Fig. 4 is the current spectrum schematic diagram adopting the noise suppressing method of the frequency converting air-conditioner compressor of the embodiment of the present invention to carry out filtered direct-axis current Id and quadrature axis current Iq; And

Fig. 5 does not add the direct-axis current Id of twin-T network trapper and the current spectrum schematic diagram of quadrature axis current Iq.

Reference numeral:

Current sample module 10, position estimator 20, velocity correction module 30, first coordinate transferring 40, first twin-T network trapper 50, second twin-T network trapper 60, current correction module 70, second coordinate transferring 80, compressor 90, clarke coordinate transformation unit 401, park coordinate transformation unit 402, inverse park coordinate transformation unit 801 and inverse clarke coordinate transformation unit 802.

Embodiment

Be described below in detail embodiments of the invention, the example of described embodiment is shown in the drawings, and wherein same or similar label represents same or similar element or has element that is identical or similar functions from start to finish.Being exemplary below by the embodiment be described with reference to the drawings, only for explaining the present invention, and can not limitation of the present invention being interpreted as.

Disclosing hereafter provides many different embodiments or example is used for realizing different structure of the present invention.Of the present invention open in order to simplify, hereinafter the parts of specific examples and setting are described.Certainly, they are only example, and object does not lie in restriction the present invention.In addition, the present invention can in different example repeat reference numerals and/or letter.This repetition is to simplify and clearly object, itself does not indicate the relation between discussed various embodiment and/or setting.In addition, the various specific technique that the invention provides and the example of material, but those of ordinary skill in the art can recognize the property of can be applicable to of other techniques and/or the use of other materials.In addition, fisrt feature described below second feature it " on " structure can comprise the embodiment that the first and second features are formed as directly contact, also can comprise other feature and be formed in embodiment between the first and second features, such first and second features may not be direct contacts.

In describing the invention, it should be noted that, unless otherwise prescribed and limit, term " installation ", " being connected ", " connection " should be interpreted broadly, such as, can be mechanical connection or electrical connection, also can be the connection of two element internals, can be directly be connected, also indirectly can be connected by intermediary, for the ordinary skill in the art, the concrete meaning of above-mentioned term can be understood as the case may be.

With reference to description below and accompanying drawing, these and other aspects of embodiments of the invention will be known.Describe at these and in accompanying drawing, specifically disclose some particular implementation in embodiments of the invention, representing some modes of the principle implementing embodiments of the invention, but should be appreciated that the scope of embodiments of the invention is not limited.On the contrary, embodiments of the invention comprise fall into attached claims spirit and intension within the scope of all changes, amendment and equivalent.

The method describing harmonic wave in existing filtering electric current was summarized first before describing the compressor control system of convertible frequency air-conditioner and the noise suppressing method of frequency converting air-conditioner compressor proposed according to the embodiment of the present invention.

In prior art, the method reducing current harmonics has a lot, such as low-pass filtering, high-pass filtering, bandpass filtering, bandreject filtering etc.Wherein, the filtering method of conventional current harmonics adopts low pass filter, and the feature of low pass filter is: to the noise higher than cut-off frequency, along with the increase attenuation multiple of frequency increases gradually, and delayed phase also increases thereupon.For compressor of air conditioner, the harmonic components of electric current concentrates near several Frequency point, such as 400Hz, 600Hz, 1200Hz, instead of whole high frequency band.Therefore, low pass filter is not the preferred plan of compressor of air conditioner noise suppressed.

In convertible frequency air-conditioner technical field, in order to improve the voltage utilization of power supply, most compressors of air conditioner adopts vector control strategy, and the load of compressor of air conditioner has periodic load characteristic, therefore in current harmonics frequency spectrum based on 2 times, 3 times, 6 primary current harmonic waves.

Inventor is surprised to find when carrying out many experiments, for 2 times, 3 times, 6 primary current harmonic waves in current harmonics frequency spectrum, the current harmonics of twin-T network trapper to characteristic frequency point is adopted to carry out trap process, can filtering 3 times, 6 primary current harmonic waves effectively, thus effectively reduce the electromagnetic noise of compressor, and large delayed phase can not be produced to system.Wherein, the transfer function of twin-T network trapper is as follows:

$D\left(S\right)=\frac{{\left(\frac{S}{{\mathrm{\ω}}_0}\right)}^2+1}{{\left(\frac{S}{{\mathrm{\ω}}_0}\right)}^2+K\frac{S}{{\mathrm{\ω}}_0}+1}---\left(1\right)$

Wherein, ω ₀for trap frequency point, the size of Monomial coefficient K decides the width of filtering well head, and K value larger trap well head is wider, but phase delay is also larger.

The compressor control system of convertible frequency air-conditioner and the noise suppressing method of frequency converting air-conditioner compressor that propose according to the embodiment of the present invention are described with reference to the accompanying drawings.

Fig. 1 is the control principle schematic diagram of the compressor control system of convertible frequency air-conditioner according to the embodiment of the present invention.As shown in Figure 1, the compressor control system of this convertible frequency air-conditioner comprises: current sample module 10, position estimator 20, velocity correction module 30, first coordinate transferring 40, first twin-T network trapper 50, second twin-T network trapper 60, current correction module 70, second coordinate transferring 80.Wherein, current sample module 10 for three-phase current Ia, Ib, Ic of Sampling Compression machine, position estimator 20 for the position of the rotor of estimating compressor and speed with the estimating speed of the estimation angle and rotor that obtain rotor.Velocity correction module 30 is for carrying out velocity correction to obtain quadrature axis target current Iqref according to target velocity Vref to the estimating speed of rotor.First coordinate transferring 40 is for carrying out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq to three-phase current Ia, Ib, Ic.First twin-T network trapper 50 is for the harmonic wave in filtering direct-axis current Id, and the second twin-T network trapper 60 is for the harmonic wave in filtering quadrature axis current Iq.Current correction module 70 is for carrying out current correction to obtain direct-axis voltage Vd and quadrature-axis voltage Vq to the direct-axis current Id after filtering harmonic wave and quadrature axis current Iq respectively according to d-axis target current Idref and quadrature axis target current Iqref.Second coordinate transferring 80 is for carrying out Coordinate Conversion to obtain three-phase voltage Va, Vb, Vc of controlling compressor to direct-axis voltage Vd and quadrature-axis voltage Vq.

In one particular embodiment of the present invention, velocity correction module 30 and current correction module 70 all can adopt pi regulator.

As shown in Figure 2, the second coordinate transferring 80 comprises inverse park coordinate transformation unit 801 and inverse clarke coordinate transformation unit 802.Inverse park coordinate transformation unit 801 carries out inverse park Coordinate Conversion to obtain two phase voltage Valpha, Vbeta for the estimation angle according to rotor to direct-axis voltage Vd and quadrature-axis voltage Vq, namely say, according to the estimation angle of rotor, two cordic phase rotators with rotor flux synchronous rotary are converted to the stator static coordinate of two-phase.Inverse clarke coordinate transformation unit 802, for carrying out inverse clarke Coordinate Conversion to two phase voltage Valpha, Vbeta to obtain three-phase voltage Va, Vb, Vc, is namely sayed, the stator static coordinate of two-phase is converted to the stator static coordinate of three-phase.

As shown in Figure 2, the first coordinate transferring 40 comprises clarke coordinate transformation unit 401 and park coordinate transformation unit 402.Clarke coordinate transformation unit 401, for carrying out clarke Coordinate Conversion to obtain biphase current Ialpha, Ibeta to three-phase current Ia, Ib, Ic, is namely sayed, the stator static coordinate of three-phase is converted to the stator static coordinate of two-phase.Park coordinate transformation unit 402 carries out park Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq for the estimation angle according to rotor to biphase current Ialpha, Ibeta, namely say, the stator static coordinate of two-phase is converted to two cordic phase rotators with rotor flux synchronous rotary according to the estimation angle of rotor.

Further, position estimator 20 for the position of the rotor according to two phase voltage Valpha, Vbeta and biphase current Ialpha, Ibeta estimating compressor 90 and speed with the estimating speed of the estimation angle and rotor that obtain rotor.

Wherein, as shown in Figure 2, the first twin-T network trapper 50 is d axle twin-T network trapper, and the second twin-T network trapper 60 is q axle twin-T network trapper.

In one embodiment of the invention, as shown in Figure 5, carry out harmonic analysis to the DC side electric current of sampling and direct-axis current Id and quadrature axis current Iq, d axle, q shaft current harmonic wave are based on 2,3,6 times of input speed electricity frequency.Wherein, input speed is 100Hz(and 1600rpm), because compressor is 2 to pole, therefore electric frequency is 200Hz.As shown in Figure 5, abscissa is frequency, and unit is Hz, and ordinate is energy, and unit is Mag ²the current harmonics of Hz, direct-axis current Id and quadrature axis current Iq is based on 2 times, 3 times, 6 times of input speed electricity frequency, namely in current harmonics frequency spectrum based on 2 times, 3 times, 6 primary current harmonic waves.

According to the principle of vector control, the ac phase voltage of output is first-harmonic and the superposing of 3 subharmonic, and through rotation of coordinate to DC side, first-harmonic becomes direct current, and 3 subharmonic become 2 subharmonic, so the first-harmonic of DC side and 2 subharmonic are effective frequencies.Therefore, 3,6 subharmonic in filtering direct-axis current Id and quadrature axis current Iq are only needed can to reach the object reducing compressor noise.

Particularly, in an embodiment of the present invention, filtered by 3 times in the first twin-T network trapper 50 couples of direct-axis current Id, 6 primary current harmonic waves and in the second twin-T network trapper 60 couples of quadrature axis current Iq 3 times, 6 primary current harmonic waves filter.

Wherein, transfer function when the first twin-T network trapper 50 and the second twin-T network trapper 60 carry out filtering to the triple-frequency harmonics in direct-axis current Id and quadrature axis current Iq respectively can obtain according to following formula:

$D_3\left(S\right)=\frac{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+K\frac{5S}{\mathrm{n\π}}+1}---\left(2\right)$

Wherein, K is the regulatory factor of notch filter.

Further, transfer function when the first twin-T network trapper 50 and the second twin-T network trapper 60 carry out filtering to the fifth overtone in direct-axis current Id and quadrature axis current Iq respectively obtains according to following formula:

$D_6\left(S\right)=\frac{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+K\frac{5S}{2\mathrm{n\π}}+1}---\left(3\right)$

Wherein, K is the regulatory factor of notch filter.

In an embodiment of the present invention, the width of the filtering well head of the first twin-T network trapper 50 and the second twin-T network trapper 60 can be determined according to K, and K value larger trap well head is wider, but phase delay is also larger.

According to the compressor control system of the convertible frequency air-conditioner that the embodiment of the present invention proposes, by three-phase current Ia, Ib, Ic of current sample module samples compressor, and utilize the position of the rotor of position estimator estimating compressor and speed with the estimating speed of the estimation angle and rotor that obtain rotor, thus velocity correction module carries out velocity correction to obtain quadrature axis target current Iqref according to target velocity to the estimating speed of rotor, also pass through the first coordinate transferring to three-phase current Ia simultaneously, Ib, Ic carries out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq, and by the harmonic wave in the first twin-T network trapper and the second twin-T network trapper difference filtering direct-axis current Id and the current harmonics in quadrature axis current Iq, thus current correction module carries out current correction to obtain direct-axis voltage Vd and quadrature-axis voltage Vq to the direct-axis current Id after filtering harmonic wave and quadrature axis current Iq respectively according to d-axis target current Idref and quadrature axis target current Iqref, and then, second coordinate transferring carries out Coordinate Conversion to obtain the three-phase voltage Va controlling compressor to direct-axis voltage Vd and quadrature-axis voltage Vq, Vb, Vc.Therefore, the compressor control system of convertible frequency air-conditioner of the present invention can current harmonics particularly 3 times, 6 primary current harmonic waves in filtering direct-axis current Id and quadrature axis current Iq, effectively suppress the noise of the compressor of convertible frequency air-conditioner, improve the comfort level of air-conditioning, and do not need to increase hardware cost, realize simple, resources of chip occupancy is low.

Fig. 3 is the flow chart of the noise suppressing method of frequency converting air-conditioner compressor according to the embodiment of the present invention.As shown in Figure 3, the noise suppressing method of this frequency converting air-conditioner compressor comprises the following steps:

S1, samples to three-phase current Ia, Ib, Ic of compressor.

S2, carries out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq to three-phase current Ia, Ib, Ic.

That is, first, by clarke Coordinate Conversion, three-phase current Ia, Ib, Ic are carried out Coordinate Conversion to obtain biphase current Ialpha, Ibeta, then, again by park Coordinate Conversion, the estimation angle according to rotor carries out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq to biphase current Ialpha, Ibeta.

S3, carries out filtering to suppress noise during compressor operating to the harmonic wave in direct-axis current Id and quadrature axis current Iq respectively based on the first twin-T network trapper and the second twin-T network trapper.

Particularly, in one embodiment of the invention, suppose that input speed is n, unit is rpm.Then the electric frequency Elec_Fre of input speed can obtain according to following formula:

Elec_Fre=2×n60 （4）

The trap frequency point Trap6 of the trap frequency point Trap3 and 6 subharmonic that can obtain 3 subharmonic according to formula (4) is respectively:

Trap3=2×n60×3×2×π （5）

Trap6=2×n60×6×2×π （6）

Wherein, 2 × π factor is the conversion factor of Hz to rad/s.

In step s3, when carrying out filtering to the triple-frequency harmonics in direct-axis current Id and quadrature axis current Iq, according to formula (1) and formula (5), the transfer function of the first twin-T network trapper and the second twin-T network trapper obtains according to following formula:

$D_3\left(S\right)=\frac{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+K\frac{5S}{\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

When carrying out filtering to the fifth overtone in direct-axis current Id and quadrature axis current Iq, according to formula (1) and formula (6), the transfer function of the first twin-T network trapper and the second twin-T network trapper obtains according to following formula:

$D_6\left(S\right)=\frac{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+K\frac{5S}{2\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

In one particular embodiment of the present invention, with ASM108D11UEZ compressor for controlled device, adopt vector control strategy, by carrying out spectrum analysis to direct-axis current Id and quadrature axis current Iq, thus the effect that inspection adopts the electromagnetic noise of noise suppressing method to compressor of above-mentioned frequency converting air-conditioner compressor to suppress.

Particularly, input speed is 100Hz(and 1600rpm), because compressor is two to pole, therefore electric frequency is 200Hz.After adding the twin-T network trapper of 3 frequencys multiplication, 6 frequencys multiplication, acquisition direct-axis current Id as shown in Figure 4 and the current spectrum schematic diagram of quadrature axis current Iq, wherein abscissa is frequency, and unit is Hz, and ordinate is energy, and unit is Mag ²hz.Fig. 5 does not add the direct-axis current Id of twin-T network trapper and the current spectrum schematic diagram of quadrature axis current Iq.From Fig. 4 and Fig. 5 relatively, after the twin-T network trapper adding 3 frequencys multiplication, 6 frequencys multiplication, 3 subharmonic of direct-axis current Id and quadrature axis current Iq and 6 subharmonic have had obvious decay, effectively inhibit the current harmonics of characteristic frequency point, thus effectively inhibit the electromagnetic noise that these harmonic waves produce.

According to the noise suppressing method of the frequency converting air-conditioner compressor that the embodiment of the present invention proposes, by sampling to three-phase current Ia, Ib, Ic of compressor, and Coordinate Conversion is carried out to obtain direct-axis current Id and quadrature axis current Iq to three-phase current Ia, Ib, Ic, thus respectively filtering is carried out to suppress electromagnetic noise during compressor operating to the current harmonics in direct-axis current Id and quadrature axis current Iq based on the first twin-T network trapper and the second twin-T network trapper.Therefore, current harmonics especially 3 times, 6 subharmonic during the noise suppressing method of frequency converting air-conditioner compressor of the present invention effective filtering compressor operating in direct-axis current Id and quadrature axis current Iq, thus suppress the noise of the compressor of convertible frequency air-conditioner, improve the comfort level of air-conditioning.Further, the method is simple and reliable.

Describe and can be understood in flow chart or in this any process otherwise described or method, represent and comprise one or more for realizing the module of the code of the executable instruction of the step of specific logical function or process, fragment or part, and the scope of the preferred embodiment of the present invention comprises other realization, wherein can not according to order that is shown or that discuss, comprise according to involved function by the mode while of basic or by contrary order, carry out n-back test, this should understand by embodiments of the invention person of ordinary skill in the field.

In flow charts represent or in this logic otherwise described and/or step, such as, the sequencing list of the executable instruction for realizing logic function can be considered to, may be embodied in any computer-readable medium, for instruction execution system, device or equipment (as computer based system, comprise the system of processor or other can from instruction execution system, device or equipment instruction fetch and perform the system of instruction) use, or to use in conjunction with these instruction execution systems, device or equipment.With regard to this specification, " computer-readable medium " can be anyly can to comprise, store, communicate, propagate or transmission procedure for instruction execution system, device or equipment or the device that uses in conjunction with these instruction execution systems, device or equipment.The example more specifically (non-exhaustive list) of computer-readable medium comprises following: the electrical connection section (electronic installation) with one or more wiring, portable computer diskette box (magnetic device), random-access memory (ram), read-only memory (ROM), erasablely edit read-only memory (EPROM or flash memory), fiber device, and portable optic disk read-only memory (CDROM).In addition, computer-readable medium can be even paper or other suitable media that can print described program thereon, because can such as by carrying out optical scanner to paper or other media, then carry out editing, decipher or carry out process with other suitable methods if desired and electronically obtain described program, be then stored in computer storage.

Should be appreciated that each several part of the present invention can realize with hardware, software, firmware or their combination.In the above-described embodiment, multiple step or method can with to store in memory and the software performed by suitable instruction execution system or firmware realize.Such as, if realized with hardware, the same in another embodiment, can realize by any one in following technology well known in the art or their combination: the discrete logic with the logic gates for realizing logic function to data-signal, there is the application-specific integrated circuit (ASIC) of suitable combinational logic gate circuit, programmable gate array (PGA), field programmable gate array (FPGA) etc.

Those skilled in the art are appreciated that realizing all or part of step that above-described embodiment method carries is that the hardware that can carry out instruction relevant by program completes, described program can be stored in a kind of computer-readable recording medium, this program perform time, step comprising embodiment of the method one or a combination set of.

In addition, each functional unit in each embodiment of the present invention can be integrated in a processing module, also can be that the independent physics of unit exists, also can be integrated in a module by two or more unit.Above-mentioned integrated module both can adopt the form of hardware to realize, and the form of software function module also can be adopted to realize.If described integrated module using the form of software function module realize and as independently production marketing or use time, also can be stored in a computer read/write memory medium.

The above-mentioned storage medium mentioned can be read-only memory, disk or CD etc.

In the description of this specification, specific features, structure, material or feature that the description of reference term " embodiment ", " some embodiments ", " example ", " concrete example " or " some examples " etc. means to describe in conjunction with this embodiment or example are contained at least one embodiment of the present invention or example.In this manual, identical embodiment or example are not necessarily referred to the schematic representation of above-mentioned term.And the specific features of description, structure, material or feature can combine in an appropriate manner in any one or more embodiment or example.

Although illustrate and describe embodiments of the invention, for the ordinary skill in the art, be appreciated that and can carry out multiple change, amendment, replacement and modification to these embodiments without departing from the principles and spirit of the present invention, scope of the present invention is by claims and equivalency thereof.

Claims (10)

1. a compressor control system for convertible frequency air-conditioner, is characterized in that, comprising:

Current sample module, for three-phase current Ia, Ib, Ic of Sampling Compression machine;

Position estimator, for estimating that the position of the rotor of described compressor and speed are with the estimating speed of the estimation angle and rotor that obtain rotor;

Velocity correction module, for carrying out velocity correction to obtain quadrature axis target current Iqref according to described target velocity to the estimating speed of described rotor;

First coordinate transferring, for carrying out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq to described three-phase current Ia, Ib, Ic;

First twin-T network trapper and the second twin-T network trapper, described first twin-T network trapper is used for the harmonic wave in direct-axis current Id described in filtering, and described second twin-T network trapper is used for the harmonic wave in quadrature axis current Iq described in filtering;

Current correction module, for carrying out current correction to obtain direct-axis voltage Vd and quadrature-axis voltage Vq to the direct-axis current Id after filtering harmonic wave and quadrature axis current Iq respectively according to d-axis target current Idref and described quadrature axis target current Iqref;

Second coordinate transferring, for carrying out Coordinate Conversion to obtain three-phase voltage Va, Vb, Vc of controlling described compressor to described direct-axis voltage Vd and quadrature-axis voltage Vq.

2. the compressor control system of convertible frequency air-conditioner as claimed in claim 1, it is characterized in that, transfer function when described first twin-T network trapper and the second twin-T network trapper carry out filtering to the triple-frequency harmonics in described direct-axis current Id and quadrature axis current Iq respectively obtains according to following formula:

$D_3\left(S\right)=\frac{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+K\frac{5S}{\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

3. the compressor control system of convertible frequency air-conditioner as claimed in claim 1, it is characterized in that, transfer function when described first twin-T network trapper and the second twin-T network trapper carry out filtering to the fifth overtone in described direct-axis current Id and quadrature axis current Iq respectively obtains according to following formula:

$D_6\left(S\right)=\frac{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+K\frac{5S}{2\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

4. the compressor control system of convertible frequency air-conditioner as claimed in claim 2 or claim 3, it is characterized in that, the width of the filtering well head of described first twin-T network trapper and the second twin-T network trapper is determined according to K.

5. the compressor control system of convertible frequency air-conditioner as claimed in claim 1, it is characterized in that, described second coordinate transferring comprises:

Inverse park coordinate transformation unit, carries out inverse park Coordinate Conversion to obtain two phase voltage Valpha, Vbeta for the estimation angle according to described rotor to described direct-axis voltage Vd and quadrature-axis voltage Vq;

Inverse clarke coordinate transformation unit, for carrying out inverse clarke Coordinate Conversion to obtain described three-phase voltage Va, Vb, Vc to described two phase voltage Valpha, Vbeta.

6. the compressor control system of convertible frequency air-conditioner as claimed in claim 5, it is characterized in that, described first coordinate transferring comprises:

Clarke coordinate transformation unit, for carrying out clarke Coordinate Conversion to obtain biphase current Ialpha, Ibeta to described three-phase current Ia, Ib, Ic;

Park coordinate transformation unit, carries out park Coordinate Conversion to obtain described direct-axis current Id and quadrature axis current Iq for the estimation angle according to described rotor to described biphase current Ialpha, Ibeta.

7. the compressor control system of convertible frequency air-conditioner as claimed in claim 5, it is characterized in that, described position estimator is used for estimating that the position of the rotor of described compressor and speed are with the estimating speed of the estimation angle and described rotor that obtain described rotor according to described two phase voltage Valpha, Vbeta and described biphase current Ialpha, Ibeta.

8. a noise suppressing method for frequency converting air-conditioner compressor, is characterized in that, comprises the following steps:

S1, samples to three-phase current Ia, Ib, Ic of compressor;

S2, carries out Coordinate Conversion to obtain direct-axis current Id and quadrature axis current Iq to described three-phase current Ia, Ib, Ic;

S3, carries out filtering to suppress noise during described compressor operating to the harmonic wave in described direct-axis current Id and quadrature axis current Iq respectively based on the first twin-T network trapper and the second twin-T network trapper.

9. the noise suppressing method of frequency converting air-conditioner compressor as claimed in claim 8, it is characterized in that, in step s3, when carrying out filtering to the triple-frequency harmonics in described direct-axis current Id and quadrature axis current Iq, the transfer function of described first twin-T network trapper and the second twin-T network trapper obtains according to following formula:

$D_3\left(S\right)=\frac{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{\mathrm{n\π}}\right)}^2+K\frac{5S}{\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.

10. the noise suppressing method of frequency converting air-conditioner compressor as claimed in claim 8, it is characterized in that, in step s3, when carrying out filtering to the fifth overtone in described direct-axis current Id and quadrature axis current Iq, the transfer function of described first twin-T network trapper and the second twin-T network trapper obtains according to following formula:

$D_6\left(S\right)=\frac{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+1}{{\left(\frac{5S}{2\mathrm{n\π}}\right)}^2+K\frac{5S}{2\mathrm{n\π}}+1}$

Wherein, K is the regulatory factor of notch filter.